The trick to containerization is picking the right workload (as with most things). Think about data, its state and where it lives and whether there are any benefits to running as a container.

Both Ubiquiti’s NVR and Plex’s media server software run’s some base application, this app within its own container then maps to data (which can exist outside the instance) that is consistent.

The fun continues when you can update a container (updating the running application), but keeping the data intact at another location. This can really help with version control etc where you can sometimes just point the new container at the data and turn off the old instance. Rollback? easy. Turn off new container and roll back to old.

Of course things are easier if you are running applications that do not change the data. Both NVR and Plex only index and capture new data (in consistant format), which makes moving between application versions much easier.

The nature of containerization means that the full power of the host is taken into regard. This is different to regular visualization where each guest is limited to the virtual hardware it is assigned. There are of course challenges where resource is congested, but this can also happen in the latter (cpu scheduling, under / over allocation of resources).

Availability also has to be built with containers in mind, with load balances and instances across multiple hosts.

Update : this site has now now been migrated from a VM to 2 x docker containers…. One for MySQL Backend and one for WordPress FrontEnd. Containers can be linked – so the WordPress container can access MySQL container via its own local port. Very cool.

There are some changes with Nested Virtualization in vSphere 5.1 also officially known as VHV (Virtual Hardware-Assisted Virtualization). If you are using vSphere 5.0 to run Nested ESXi or other nested Hypervisors, then please take a look at the instructions in this article. With vSphere 5.1, there have been a few minor changes to enable VHV.

The new Virtual Hardware 9 compatibility will be required when creating your nested ESXi VM, Virtual Hardware 8 will not work if you are running ESXi 5.1 on your physical host. You will still need to enable promiscuous mode on the portgroup that will be used for your nested ESXi VM for network connectivity.

vhv.allow = “true” is no longer valid for ESXi 5.1 to enable VHV. A new parameter has been introduced called vhv.enable = “true” that is now defined on a per VM basis to provide finer granularity of VHV support. This also allows for better portability between VMware’s hosted products such as VMware Fusion and Workstation as they also support the vhv.enable parameter.

You can now enable VHV on a per VM basis and using the new vSphere Web Client which basically adds the vhv.enable = “true” parameter to the VM’s .VMX configuration file.

There is a bug in the tg3 driver on the ESXi hosts (1gbit broadcom cards in the new hosts). If the network card is put under load and netqueue is enabled it will sometimes decide to drop all traffic. Essentially i’ve disabled netqueue and the problems have gone away…. as per this vm kb :

You might be able to do this via “host profiles” but if you do not have the licensing for it, this is the alternative. Very handy if you have over 50 or so port groups. It can be re-run to add to additional hosts as needed.

Install powercli, run the following to obtain your current list of virtual port groups off existing host;

Get-VirtualPortGroup -VirtualSwitch vSwitch0 -VMHost esx-01

Grab the output and place into CSV file or copy straght into Excel…

Following the formatting of the following “esx_switching-generic.csv” import the required data from aboves output. Note : the top line is the headers and should always be at the top of the CSV file.

#This script is designed to allow you to configure switches on multiple hosts by
#importing information from a prepopulated .csv file. vMotion switch created based
#on Mike Laverick's posting http://www.rtfm-ed.co.uk/?p=1514
#!!!!!!!Values passed for Type are Case sensitive since comparisons are being made.!!!!!!!

#Gets Switch object based on the value for SwitchName (required for several cmd-lets that do not accept Strings)
#'If' statement is used since a vMotion type does not already have a switch configured which will throw up an error.
If ($Type -ne "vMotion") {
$getswitch = Get-VirtualSwitch -VMHost $gethost -Name $SwitchName
}

# v3 : grab all alarms from vcenter (so should work all versions) and use these for alarm variables
# Usage ;
# Please manually connect to vCenter, use "Connect-VIServer" -- this promotes usernames and passwords not beings saved with script.
# Any alarm that is currently active will send email alert -- please confirm appropriate values for tiggers before running this script.

UPDATE : I generally use the following script now. Less to maintain, and covers any alarms that have not been managed.

# Author : Darren Taylor
# v5 : grab all alarms from vcenter (so should work all versions) and use these for alarm variables
# Usage ;
# Please manually connect to vCenter, use “Connect-VIServer” — this promotes usernames and passwords not being saved with script.
# Any alarm that is currently active will send email alert — please confirm appropriate values for tiggers before running this script.
#
# Note ;
# This script needs to be modified to exclude alarms that are not critical (exclusive rather than inclusive)
# Once Exceptions list is updated, re-run script.

# ——————- VARIABLES ————————-

#Set Notification emails here;
$MailTo= “vcenter@company.com”

# These are the names of the alarms to ignore — i.e. do NOT setup email alert
# THESE ALARMS ARE CONSIDERED NON CRITICAL
$Exceptions= `
“Virtual machine cpu usage”,`
“Virtual machine memory usage”